Adjust number of digits displayed for timer property?
There is an option with quite a few Logic Bricks, but 

formatting.py:

def propertyToText(controller):    
    sensor = controller.sensors[0]
    propertyName = sensor.propName
    owner = controller.owner
    value = owner[propertyName]

    formattedValue = "{:.2f}".format(value)

    owner.text = formattedValue


Usage:
Have a Property (e.g. timer)

Property Sensor [enable True Level Triggering] 
Mode:Changed Property: your property

--> Python Controller Module:formatting.propertyToText